Sealing device



1,616,423 F 1 v 1927- v. F. SLEZAK I SEALING DEVICE Original Filec'i March 24, 192

Patented Feb. 1, 1927.

' UNITED STATES PATENT OFFICE.

VINCENT r. SLEZAK, or CHICAGO, ILLINOIS.

' SEALING DEVICE.

Original application filed March 24. 1926, Serial No. 97,034. Divided and this application filed August 2,

1926. Serial No. 126.671.

This invention relates to improvements in weighing machines, and more particularly bears upon the sealing device for calibrating the machine for accurate reading.

It has 'heretoforebeen proposed to provide various types of tran'sn'iission mecha nisms for transferring the energy of movement of a platform under the actuation of a weight to be measured into an indicating device. It is mechanically difficult, 1f not 1mpossi-ble, to make all parts of such machines themselves so that one part identical amon d by its congener without dismay be replace turbance of the accuracy of the indication.

For reasons of quick and easy manufacture it has therefore been customary to provide means for regulating the machine so that any initial irregularities are compensated and the final indication at the indicating instrumentality is an accurate statement of the weight to be measured.

The presentginvention proposes a characteristic and peculiar transmitting mecha-- nism for the delivery of an indication when aweight to be measured is placed upon the machine. This mechanism has already been described anddisclosed in my copending apwill appear in the course of the following specification and claims.

On the accompanying drawings:

' Fig. 1 is an elevation of the mechanism in a weight supporting and indicating position, at approximately two-thirds of the capacity of the weighing machine.

Fig. 2 is a similar view in the position of rest or of no load.

7 Referring in detail to these drawings, the main supporting plate 15 represents the same element as in my aforesaid pending application and constitutes a part of the machine frame which is rigidly supported against movement and upon which the various operative members are mounted. The

weighing platform .may be of the type shown in my copending application and serves when a weight is superimposed there the weighing rod 37 and since the latter distorts the springs 36 in pro ortion to the weight to be measured, the lin 32 moves in accordance therewith.

Pivotally mounted at a fixed point 29 of the plate 15 is the swinging link 28. The sealing segment or cam plate 26 is connected to the weighing link 32 and the swinging link 28 by a common pivot member 27 about which it may rock. It will be under stood that the axis of the pivot 27 is substantially the center of the arcuate upper edge of cam surface 26* of the sealing segment 26. The offset slotted arm 30 projects from the sealing segment 26 and constitutes.

a moving guide pivot for the sealing segment 26 by its engagement with a pin 31 which is fixedon the plate 15. A rack bar 23 is guided for vertical movement upon the plate 15. At its lower end this rack bar has a projecting pin 25 which carries an antifriction roller 25 This roller rests u on the upper edge of cam surface 26 of t e sealing segment. The upper end of the rack 23 has teeth to engage with a pinion 22 which is s lined to the shaft 22 of an indicating mec anism such as a dial of the rinting wheel shown in my copending app ication since the particular type of indicating mechanism employed is not of the essence of this invention, it will be indicated convention ally as being .mounted upon the shaft 22 and located on the opposite side of the plate 15. A suitable bearing and support 19 s provided for the rack and the pinion so that they remain in engagement and make exact and proportionate movements.

A guard plate 26? is bolted to the face of the sealing segment 26 and is provided with a slot which is arcuate about the axis of the pivot 27, and receives with a slight amount of play the antifriction roller 25 supported on the rack 23. This guard plate 26 has a guard member 26 which is adapted to be brought into contact with the upper surface of this antifriction roller for the purpose to be set forth hereinafter. The lower edge of the slot is below the cam surface, so that it does notinterfere with the contact of the roller 25 therewith.

The method of operation of the device is as follows: lVhen a weight to be measured is placed upon the machine platform, the weighing rod 37 will pull downward on the springs 36 until an equllibrium is established.

During this downward movement of the bracket 34, the weighing link 32 pulls downward upon the sealing segment and causes the latter to move bodily downward. During this movement of the segment, the en-. gagement of the pin 31 in the slotted arm 30 of the segment will cause the latter to the sector plate it is supported against an uncontrolled rocking movement by the swinging link 28.

The rack bar 23 is of sufiicient weight and is so designed in its supports and guide that it falls by gravity when the sealing segment has been removed awa from beneath it. It thus follows the sea ing segment in its movement, but is not positively connected thereto. The antifriction roller 25 on this rack 23 will rest substantially at the topmost art of the cam 26*. The pinion 22 is move by this rack in its downward gravitational movement to deliver the weighing indication.

Owing to differences in the springs which may be employed in such structures, as set forth above, the sealing segment may not have been moved to a proper position to indicate the correct measure of the weight upon the platform. An arbitrary adjustment is necessary for this; which is provided according to this invention by properly shaping the cam surface 26; It will be seen that this cam surface is at the top and easily visible to the assembler. Standard weights are placed upon the platform and the position of the indicating instrument for each weight is determined. The weighing springs 36 are then adjusted until for every weight within the capacity of the'machine, the indication is justcorrect or is too low. One standard weight such as 50 lbs. is then placed upon the platform, and the deviation of the indicating instrument. from a registry of 50 lbs. is noted, and then the segment 26 has its cam surface 26 filed away until the antifriction roller 25*, when seated in this newly calibrated position, will cause the indicating mechanism toregistry accurately. A similar calibration is made for other weights, until the cam surface 26 will at any position accord a correct registration at the indicating instrument.

This work of calibration is facilitated by the ready access'and easy inspection afforded to this cam surface.

When a device is employed with a coin controlled weighing machine as shown in my copending application, it has been found that especially at the higher weights, the rack 23 in its slow gravitational movement some times requires an excessive time for the indicating instrument to register its final position. In order to positively draw the rack downward into an approximately correct location, the guard plate 26 is provided.

In the position of no load or atjrest, as shown in Fig. 2, the antifriction roller 25 is resting against the left hand end of the cam surface of the sealing segment 26 When a heavy load is placed upon the weighing platform, the weighing link 32 is drawn downward as before, and the sealing segment 26 moves bodily away from the antifriction roller 25. 'The guard member 26, however, engages the upper surface of this antifriction roller and by it draws the rack 23 downward so that the indicating instrument gives an approximately correct measurement. Since, however, some force is re quired for this which has not been applied to the springs 36, and which will vary according to the weight and the conditions of load, it is apparent that this is merely a bringing into an approximately correct position. This movement occurs in a short interval of time after the weight has been placed on the machine. The rack 23 may new fall under thcaction of gravity until the antifriction roller 25 is presented again against the upper surface of the sealing segment 26, at which an accurate calibrated indication will be afforded. The antifriction roller therefore cooperates both with the cam surface 26 and the guard members 26.

When the weight is removed from the weighing platform, the weighin link 32 will be forced upward by the action of the weighing springs 36 and in turn the seal ing segment 26 will deliver an upward thrust against the antifriction roller 25 and there by restore the rack 23 and the indicating instrument to its zero position.

The invention is not limited to the specific form of embodiment shown, but may be modified within the scope of the appended claims. i

I claim:

1. In a sealing apparatus for weighing machines having weighing springs and length by said member according nected to said link, a driving means to distort the same in proportion to:

the weight to be measured and a device to indicate such weight; a link having a. fixed pivot, a link pivoted to and moving with said distortin means, aplate pivoted to the other en s of said links and having a slot therein, a pin on the machine framereceived in said slot to guide the links and plate during the actuation of the 'distorting means, said late having a cam surface at the top edge t ereof, and a member'resting by gravity on said cam surface for actuating said indicating device, the camsurface being calibrated to establish the acweight to be measured, a cam formed that said instrumentality accurate- 1y indicates the weight acting upon said member.

3. In a movement transmitting mechanism for weighing machines having a member actuated by the weight to be measured and an indicating instrumentality, a link moved substantially in the direction of its own length by said member accordin -to the weight to be measured, a cam p ate connected" to said link, a driving device for said instrumentality supported inoperative relation with the cam on said cam plate,

means to cause said cam plate tomove during the movement of said link to present different portions of its cam to said device according to the weight to be measured and auxiliary means to guide said link an plate in their-movements, said cam, having its operative surface so conformed that said instrumentality accuratel indicates the weight acting upon said mem er.

,4. In a sealingapparatus for weighing machines having a member actuated by the weight to be measured and an indicating instrumentality with a driving pinion, a

, weighing spring connected to the machine frame, abracket connectedto the other end of said spring, a-Weighin link pivoted to said bracket, a guide lin having a fixed pivot, acam plate having a slot, a common pivot for said links and plate, a pin on the machine frame in sai slot to guide and rock the late during movement of said weighing linii, a rack meshing with said pinion and cooperating with said cam surface so that said instrumentality is caused to accurately indicate the weight upon said member, and means to, guide said rack in its movements. I i

5. In a movement transmitting mechanismfor weighin machines having a member actuated by the weight to be measured and an indicating instrumentality, a pivotally mounted sealing cam plate connected to said member so that it is rocked according to the movement thereof, a device to drive said instrumentality and resting against the cam on saidcam plate and adapted to move under the action of gravity to follow the movement of said plate, and a guard on said plate to engage sa'd device to move the latterpositively downward into approximately its final position for the weight to be measured.

6. In a movement transmitting mechanism for a weighing machine having a member actuated by a weight to be measured and an indicating instrumentality, a

plate connected to said member and moved" bodily thereby according to the weight to be measured, means to rock said plate during its bodily movement, said plate having a sealing cam surface at its top, a device to drive said instrumentality and adapted to move under the action of gravity to follow the movements of said Plate, an antifrictionroller on said device to rest against sald cam surface, and a guard on said plate to engage said roller to move the device positively downwardly into approximately its final position for the weight to be measured.

-7. In a sealing apparatus for a weighing machine having a member actuated by the weight to be measured andv indicating instrumentality with a driving pinion, a rack bar meshing with said pinion and movable in a vertical line, a sealing segment, means on said bar to rest on the upper edge of said segment, a swinging link on which said sealing segment is pivoted, a vertical bar connected to said member and pivotally connected to said sealin segment at the radial center thereof, a sotted arm' projecting from the circumference of said segment, and a fixed fulcrum pin adapted to engage the slot in said arm. I 8. A weighing machine including in combination, a,member actuated by the weightto be measured, an indicating instrumentality, a member to actuate said instrumentality, a plate pivotally connected to one of said members and having a segmental surface substantially concentric with such pivotal connection, said surface being in operative relation to said other member, and means for oscillating said plate so that a separate and definite oint of said surface is presented to said ot er member for each &

particular weight being measured, whereby said surface may be scraped for the sealing of the weighing machine for accuracy.

9. A weighing'machine including in cornbin'atlon, a member-actuated by the weight to be measured, an indicating instrumentality, a rockably and vertically bodily shiftable plate, means connecting said member and plate to shift the latter vertically bodily according to the movement of the said member, a stationary member cooperating with said plate to rock the same dur-. ing its shifting movement,'said plate having a top sealing surface, and a device resting upon said sealing surface and in engage ment therewith during the shifting and rocking of said plate to operate said instrumentality, so that said plate in its rocking movement presents a separate and definite point of said surface to said device for each particular weight being measured, whereby saidsurface may be scraped for the sealing of the weighing machine for accuracy.

10. A weighing machine including in release combination, a member actuated by the weight to be measured and guided for sub stantially rectilinear movement during suchactuation, an indicating instrumentality and an actuating member forthe same guided to move substantially in line with said actuated member, an oscillating plate pivotally connected to one of said members. and moving bodily therewith, said plate having a segmental surface thereon substantially concentric with said pivot and adapted to oper is presented to said other member for each particular weight being measured, whereby said surface may be scraped for the scaling of the weighing machine for accuracy.

In testimony whereof, I aflix my signature.

VINCENT F. SLEZAK. 

